Fast food stores typically display the names of food items and prices on signs which are provided with back lighting. The prices are displayed on modules permitting changing the price. Typically, the numbers are on pre-coiled price strips which are supported so that when one of the numbers is displayed at an aperture in a bezel, the coils at each end of the strip are theoretically spread apart behind the displayed number to permit light to enter from the light source.
In practice, however, these coils tend to close behind the displayed number and cast shadows on the number. The coils cannot be held far apart since adjacent price modules would interfere. There is not much spare space between modules. Thus, the lighting is not uniform and the displayed numbers are darker than desirable.
U.S. Pat. No. 4,095,359 discloses such a price display module. That module is an open channel which in theory allows light to pass to the front but the coils hang over the ends of the channel legs and block some light. As the coils loosen with age, they block more light.
My copending application Ser. No. 423,692 shows a light pipe arrangement which is a great improvement over the arrangement of U.S. Pat. No. 4,095,359. But cost or other reasons may rule against the light pipe.